Help a total tube amp newbie find a super simple design...

[Eli Duttman]

Any chance that you'd provide me with a schematic

I was just throwing the idea out there of using a wall wart...i figured it probably wouldn't work, but i figured, what the heck...

Thanks for all of your help!

Look here at the B+ supply used in "El Cheapo". That supply is good for 200 mA. of DC. For a lesser draw, a smaller 1:1 isolation trafo is in order. The 1:1 trafo should be rated for an AC RMS draw 4X the DC B+ draw.

 

[nerd of nerds]

AHA!!!!

Upon more reading i understand what you said dave!

Would it work to drive the el84s with some 12ax7s?

Basically what i'm wanting to do is combine the circuit that i linked to with another one i found online using JUST the 12ax7...

So one of these:

http://sub.allaboutcircuits.com/images/05307.png

Driving one of these:

http://www.tubecad.com/september99/page11.html

 

[lndm]

Thats one interesting 12ax7 circuit youve found there. It is uncommon and probably a bad one to learn from. Might I suggest you find a single el34 amp schematic that has a 12ax7 driver.

 

[Sherman]

Do a search here for Mikael's SE KT88 amp. Very simple, only 3 tubes if you build it as stereo (4 tubes if built as monoblocks). A few resistors and caps and a volume pot.

 

[kathodyne]

hey nerd of nerds!

I built that 'strange' 12AX7 circuit.....!

I wanted to build a cheap battery operated amp, it works gives way less than a watt...
HV is derived from an astable multivibrator...

For stereo you could do about 4 hours of listening with a scooter-battery (incl. heaters)

i used an opel bobine as opt!!

it sounded quite allright but nothing fancy...an autoformer is way from ideal!!!!!

never thought i'd see that one again....!
greetz !